This has almost certainly come up before but I can't find it so ...

There seems to be some discrepancy in the autosofts rules. It's not explicitly clear in any section, but in some places it is implied that drones need the autosoft to make a test and in others it doesn't. I'm thinking particularly of Clearsight, where under Drone Perception it says drones can make perception tests without it.

I can't find any exact mention anywhere that drones cannot default, but that was the impression I had. I was going by the understanding that a drone without a Maneouver autosoft can still drive/fly/walk as designed to but if a vehicle test is called for then it will fail, so general movement is fine but nothing tricky is possible. But if that's true, then what of the Clearsight example? Is it an exception where it simply adds dice whilst all the other autosofts not only add dice but actually make the roll possible in the first place?

What is the majority interpretation here?

I go with "Pilot capabilities" - Arsenal, PG 103. Also "Pilot Programs" and "Issuing Commands" - SR4A pg 245.

Making a perception test seems within a dog-brains programming because a car on autopilot has to avoid running over things. It has to be aware of potential obstacles. The clearsight simply makes better decision than a dog brain on it's own.

Note that making a perception test and doing anything as a result of that knowledge are two separate things. It may see that there's a troll with a Panther XXL aimed at the drone, but if the software specs didn't say anything about trolls with Panther XXLs, it isn't going to react to that knowledge. Here you may have to (as GM) consider the purpose of the drone. While both a Manservant and a LEBD have Pilot 3 programs, the LEBD may be a lot better at not getting shot at while the manservant is better at washing clothes. Likewise the cars under "Military, Security Medical Craft" may well have dog brains more suitable to a shadowrunner's needs.